|
|
|
|
LEADER |
02485 am a22002293u 4500 |
001 |
108101 |
042 |
|
|
|a dc
|
100 |
1 |
0 |
|a Borst, Sem
|e author
|
100 |
1 |
0 |
|a Massachusetts Institute of Technology. Department of Aeronautics and Astronautics
|e contributor
|
100 |
1 |
0 |
|a Massachusetts Institute of Technology. Laboratory for Information and Decision Systems
|e contributor
|
100 |
1 |
0 |
|a Modiano, Eytan H
|e contributor
|
100 |
1 |
0 |
|a Jagannathan, Krishna Prasanna
|e contributor
|
700 |
1 |
0 |
|a Whiting, Phil
|e author
|
700 |
1 |
0 |
|a Modiano, Eytan H
|e author
|
700 |
1 |
0 |
|a Jagannathan, Krishna Prasanna
|e author
|
245 |
0 |
0 |
|a Scheduling of multi-antenna broadcast systems with heterogeneous users
|
260 |
|
|
|b Institute of Electrical and Electronics Engineers (IEEE),
|c 2017-04-13T13:58:57Z.
|
856 |
|
|
|z Get fulltext
|u http://hdl.handle.net/1721.1/108101
|
520 |
|
|
|a We study the problem of efficiently scheduling users in a Gaussian broadcast channel with M transmit antennas and K independent receivers, each with a single antenna. We first focus on a scenario with two transmit antennas and statistically identical users, and analyze the gap between the full sum capacity and the rate that can be achieved by transmitting to a suitably selected pair of users. In particular, we consider a scheme that picks the user with the largest channel gain, and selects a second user from the next L - 1 strongest ones to form the best pair, taking channel orientations into account as well. We prove that the expected rate gap converges to 1/(L- 1) nats/symbol when the total number of users K tends to infinity. Allowing L to increase with K, it may be deduced that transmitting to a properly chosen pair of users is asymptotically optimal, while considerably reducing the feedback overhead and scheduling complexity. Next, we tackle the problem of maximizing a weighted sum rate in a scenario with heterogeneous user characteristics. We establish a novel upper bound for the weighted sum capacity, which we then use to show that the maximum expected weighted sum rate can be asymptotically achieved by transmitting to a suitably selected subset of at most MC users, where C denotes the number of distinct user classes. Numerical experiments indicate that the asymptotic results are remarkably accurate and that the proposed schemes operate close to absolute performance bounds, even for a moderate number of users.
|
546 |
|
|
|a en_US
|
655 |
7 |
|
|a Article
|
773 |
|
|
|t IEEE Journal on Selected Areas in Communications
|